Process of manufacturing churned products from milk and cream.



c. E. GRAY. PROCESS OF MANUFACTURING CHURNED PRODUCTS FROM MILK ANDCREAM.

7 APPLICATION-FILED DEC-3h 1912.

1,155,055; Pa /o entedSept. 28, 1915.

cnns'rnn EARL Gear, or non 'canrromim.

rnocnss or mannrac'runme cnumqnn PRODUCTS more MILKAND c i Specificationof Letters latent. Patentedsept. 2%, 1915.

Original application filed December 13, 1910, Serial No. 597,028.Divided and this application filed December 31, 1912.Seria1-No.-789,475. 7.

To all whom it may concern: I Be it known that I, Crms'rnn EARL GRAY,

' a citizen of the United States, 'residin at Eureka, in the county ofHumboldt and tate of California, have invented a certain new and usefulImproved Process of Manufacturing Churned Products from Milk and -Cream;and I do hereby declare the followingtobe a full, clear, and exactdescriptionof the same, referencebeing had'to the accompanying drawings,forming part of this specification, and to the letters of referencemarked thereon.

It has been generally supposed and believed that changes in flavortaking place in milk and the products of milk, especially cream andbutter, when held at ordinary temperature or at lower temperature as inrefrigeration, were produced almost Wholly by bacteria or enzymfermentation and the probability of changes which are strictly chemicaland without the aid of either bacteria or enzyms has received verylittle atf dized fats resembles in flavor very much the taken as amatter of course, and conceded as inevitable. In other words, it hasbeen conceded that if milk or cream be pasteurized or sterilized theprocess naturally will produce certain flavors which in intensity dependlargely on temperature and the length of time which the milk or cream isheated.

Referring. again to the holding of milk, cream and butter, I have. foundthat when milk or cream was pasteurized at temperatures high enough todestroy enzym action or in case of butter where the butter was made fromcream just after it had been as= teurized at" high temperatures, that won these products were placed in cold storage at temperatures low enoughtoprevnt bacterial action niaterialchanges In flavor still took'plac'e.To illustrate more fully I have held butter, made from cream which hadjust been pasteurized at 185 F. in cold storage at '-10 F., yet at thislow temperature very pronounced undesirable flavors developed; flavorstermed by butter Judges as oily, fishy and decomposed fat. Again,

cream pasteurized at temperatures sufi ciently high to destroy allenzynis and especially cream high in fat content, when butter from sweetcream giyes? held at temperatures low enough to practically inhibit theaction. of bacteria, in most cases in a short period took'on a veryundo;

cans or any other utensils in the process of handling-or manufacturingwhere iron compounds become mixed with the product, that sirableoilyflavor. It has been found that where milk or cream .is handled in rustyundesirable flavors develop in a much .shorterytime than where thesecompounds are not present. The intentional addition of variousmetallic-salts .as iron, copper, etc,

has given-similar results. It is not known that these salts acceleratethe'action of enzyms or the growth of bacteria, but rather it has beenfound that these salts, especially salts of copper, greatly retard thebacterial growth. From this it seems reasonable to believe that therewhich are not due to either bacterial or enzym action. The nature of theflavors indicates very strongly that an oxidation takes place; in otherwords, the product of oxiflavor produced in the milk, cream or butter.The fact that these flavors develop more rapidlyin the presence ofmetallic compounds would indicate that these compounds act as catalyticagents, bringing about a more rapid oxidationthan would otherwise takeplace. Atthe present time it does not appear practicable to handle milkand cream in non-metallic containers and manufacturing apparatus. Inother words, delivery containers, cream separators, pasteurizers,

ripening vats with, cooling, devices, and

are changes taking place" which does'not develop in storage the flavorsof oxidation to a ma eddegree. Asinthe case of metalliosalts 6rvmetallic com ounds it seems very prohablethat' the acid also acts as acatalytic agent. "e making ei'y satisfactory results, so far as thekeeping qualities are concerned such butter is not wholly satisfactoryon-account ofits being without the flavors characteristic of, high classbutter;

At the time the milk is drawn from the cow it passes to the pail'in suchmanner as to be continuously mixed with air. The very nature of handmilking is such thatair is very intimately incorporated with the imilk.With the milking machine, while the tendency to incorporate air may beslightly less, yet air is :very intimately incorporated. All of'theprocesses of straining, filtering and. pouring the milk from onecontainer to another tend to incorporate air. Practically all thedevices for heating and cooling milk and cream are such that air isagain incorporate li Considering the centrifugalseparator, both thecream and milk are thrown through the air from the revolvingbowl in avery finely dividedcondition against the collecting coverspf theseparator. It would 'be difiicult to devise a'machine of greaterapparent efliciency for incorporating air with milk or crea-mfthan thecentrifugal separatc-r. On account of the viscosity of the f creain'much-airi is retained in this product. This is very readilydemonstrated,.as will be later described. With practically all of themilkand cream pasteurizers and ripening vats the milk or cream is moreor 1cm intimately mixed with the air. ,The process of churning is alsoaprocess of very thoroughly mixing and incorporating air. In

most all instances in churning the cream reaches a condition where airis incorporated to the extent that the total volume of the mixture ismore than one-third'greater than the original'volume of the cream. Asthe churning progresses some of the air is given up but mu'ch'isretained in the finished butter. By the process of Working the buttermore or less air may be incorporated. To

further demonstrate that air is actually-incorporated'in milk, cream andbutter 1 have conducted the following experiments: An

ordinary 400 c.'c. beaker about'half full of fresh. cream was placedin abell jar andthe air slowly exhausted. Bubbles ofair immediately beganrising through the cream and the volume beganexpanding. By the time ava'cuumof 28 inches was produced the upper two-thirds of the volume ofcream appeared to be foam and the total'volume almost filled the beaker.Fresh milk treated in the same manner acted similarly to the I cream,however, the volume did not increase to the extent of that of the creamand less foam was produced. Undoubtedlythis difference was due to adifference in the V-E-V cosity of the two products, less air having beenretained in the fresh milk. A print of was placed in a. bell j ar. andcovered completely with freshly distilled water. Thejair was then slowlyexhausted. Small I bubbles of air were very soon noticeable all over thesurface. of the butter and as the vacuum increased the bubbles of airbecame larger and finally passed up through the' water. Cracks werenoticeable extending in various directions through the print of butterand the bubbles of air continued to rise through the water. 1 By thetime a 28 inch vacuum was produced the print of butter "was fullofcracks which were produced by the'expansion and liberation of theincorporated air. Attempts were made to pack butter in glam jars andthen pump 'a' vacuum, on the jar with the intention of sealing thebutter in partial vacuum, but this was found impracticable, due to thefact that theexpansion of the incorporated air forced-the butter out ofthe containers.

From this we have conclusive evidence that air is incorporated withmilk, cream and butter and apparently we have suificicnt reasons'tobelieve that the air exists in a very finely divided condition and invery close proximity to the other constituents. Being in possession ofthis information,

most of which comes from my own investigationof dairy products I havedevised a new and improved process for milk and its products, whichprocess has for its basis the exclusion of oxygen, especially the inti-'mately incorporated oxygen. By this procof suess I am able to produceproducts perior quality.

The object of this invention is to providea piocess for retarding thedecomposition of the constituents of milk and cream products, especiallybutter or the products from churning.

It consists substantiallyin removingthe free oxygen, especially theintimately'incorporated oxygen, by subjecting the milk or cream undersuitable conditions to a vacuum and subsequently carrying on the variousprocesses of treatment or manufacturing as opening regulated by thevalve (b) through which the milk .and cream may be intro-' duced' intothe vacuum chamber (0). (d) is an opening communicating with the vacuumpump (P) through the tubular condenser (e), the function of which willbe later described. The chamber (a) is filled not more than half full ofcream or milk the additional space being or expansion. The air presto betreated, left for foam sure is now greatly reduced by the vacuum pump,the pressure being indicated by the combination vacuum and pressure gage(g). The action of the milk or cream may be Watched through the glasswindows f) in the doors' (g). The milk may be agitated by the agitatingdevice (It) which enters.

the vacuum chamber through the stuifing box (5) and is driven by thegearing (j). The vacuum chamber is surrounded by the jacket H'eat isapplied to. the milk or boiling point of milk or cream, at the vacuummaintained, is reached. The tempera-' ture is noted by thethermometer(p). The

process ot boiling under vacuum is continued until practically all ofthe free oxygen is removed. All vapor is condensed by the condenserwhich discharges the condensed liquid back into the milk or cream in thechamber, thereby preventing 'a'change in vready to be churned.

composition, especially the water content of 'the product beingtreated.

- It has been my practice to treat milk or cream under avacuum of28inches for a period of thirty minutes, during-which time the productboilsslowly and is continually stirred by means of the agitating device.

At the eridof this period the,free oxygen has been 'suiiiciently'removed so that the products of oxidation in the final products are notnoticeable. Milk or cream is now pasteurized, or sterilized, and

Referring especially to pasteurization and sterilization the milk orcream may be pasteurized or sterilized in the apparatus described byclosing the valve (0) and apply-- ing heat in the jacket eitherby steamor hot Water and stirring by means of the agitating device, all of whichhas been previously described. By applying steam under, pressure in thejackettemperatures suficiently' high to produce sterile products, bysingle heating, may be produced such increase in temperature naturallycaus ng a proportionate increase in pressure within the chamber,inasmuch as the valveo is closed as above stated. The temperature andpressure at all times maybe noted by the thermometer and combinationpressure and vacuum gage. After pasteurization or; sterilization themilk or cream may be cooled by circulating water or other cool- .ingmedium through the acket. It is not essential that. the pasteurizationor sterilization be carried on in the apparatus as described, but it mayother suitable apparatus whereby the material incorpoi 'ation-of freeoxygen is preyented,either bv conducting the operation in vacuum, in thepresence of non-oxidizing gases, or by careful handling under atmosbeconducted in any pheric conditions whereby air isnot inc'orwiththeproducts to an extent sufficient o produce changes and undesirableflavors. To illustrate-I have) demonstrated that cream after beingtreated to remove the free oxygen can be carefully transferred ,underatmospheric conditions to suitable containers; the containers thenhermetically sealed and the cream sterilized by heating to 250 F. forthirty minutes. Such cream does not possess the undersirable flavors ofwors ed ordinary cream sterilized in this manner, is

not materially changed in flavor and is of very" excellent uality.

Separation 0 milk or cream after the removal ofthe free oxygen mayibedone y means of any centrifugal separator whlch is inclosed .in a vacuumchamber.

The centrifugal separator may be driven by an electric motor or othersuitable de-' vice within the vacuum chamber or from external powerapplied to a shaft extending through a' stufi'ing box into the vacuumchamber. Also the separation may becamried onin a similar manner butinthe presence of non-oxidizing gases. In butter 7 making, the cream ispreferably treated as has been described, pasteurized, cooled andripened. During the ripening process enough air is introduced byagitating the cream inithe presence of air to bring about a satisfactorydevelopment of the lactic acid 'producingorganisms. Such organisms beingintroduced after pasteurization and cooling injthe form of a culturetermed a starter. When the ripening has developed to the desired degreeit is advisable to again remove the oxygen from the cream by the processpreviously described. The cream is then desired temperature for churningby circulating cooling media through the jacket of the apparatus aspreviously described. When this temperature is reached the cream isintroduced into a churn'in a vacuum chamber.

and butter workers may be used with satisfactory'results. The churn andworker. are driven by an electric motor or other suitcooled, to theordinarily I Most of. the combined churns able device within thechamber, or from external power to a shaft extending through a stulfingbox into the vacuum chamber.

' Churning the cream and working the but- 1'25 and air is admitted tothe chamber and churn, as in removing butter milk introducing wash Waterfor the butterand salting the butter, etc., the vacuum chamber is lsealing butter under &

- distilled or boiled and then reduced to the desired temperaturewithout the re-incorpo ration of free oxygen. It is advisable to applythe salt in the form of brine which has been previously boiled andreduced to :the desired temperature without the incorporation of freeoxygen. After the butter .is finished it may be removed from the churnand packed in any desired package without re-incorpoi ation of freeoxygen or it may be packed in containers andsealed' 'under a partialvacuum.

heretofore pointed out vacuum in containers is not practicable withbutter made in the ordinary way. 1 L H Obviously, instead of having thechurn and worker in a vacuum chamber, as has been described, the churnbody may form a vacuum chamber. Again, instead of churning in vacuumthe-churning may be conducted in the presence of non-oxidizing gases.

For the reasons making, etc., inasmuch as when subjected to a vacuum andheat which. will boil. it at the low pressure maintained in the chamber.not only will the free oxygen be drawn 0:1 with the vapor, but the vaporwill carry off with it other undesirable substances which may havedeveloped in the cream, especially gases and volatile substances. Undersuch circumstances it will be understood, of course,'that the vapor isnot returned to the cream when condensed and it is not essential thatitbe condensed save for the advantages tobe secured thereby inprotecting the apparatus and assisting in maintaining a proper degree ofvacuum.

This application is a division of my prior application Serial No.597,028, filed December 13, 1910, for a process of manufacturingproducts from milk and cream.

Having thus described my invention what I claim as newand desire tosecure by Letters Patent of the United States, is:

1. The process of manufacturingbutter from cream, which consists inremoving the 1 incorporated free oxygen,

then sterilizing In washing the butter it is 'ad- It is obviousthat'with the apparatus'illustrated cream may be purified for butter theoxygen freed liquid and churning the same under non-oxidizingconditions.

2. The process of manufacturing butter from cream, which consists inremoving the incorporated free oxygen, then producing butter by churningthe oxygen freed cream under non-oxidizing conditions.

" 3. The process of. manufacturing butter from cream, which consists insubjecting the cream to rarefied conditions, agitation andheat towithdraw the free oxygen, then reducing the temperature andc'hurning theproduct under non-oxidizing conditions to produce butter.

4 The process of manufacturing products from milk. and cream, whichconsists in subjecting the milk and cream to rarefied conditions andheat to withdraw the free oxygen, restoring to the liquid substantiallythe percentage of liquid carried off as vapor in the process, and inchurning the product.

- 5. The process of manufacturing products from milk and cream, whichconsists in heating thesame subjected to agitation and withdrawing thefreed oxygen, then heating the same under pressure to a sterilizingtemperature, then cooling and finally churning the product withouttheincorporation of free oxygen therein.

6 The process from cream which consists incorporated free oxygen, thenproducing butter by churning the oxygen-freed cream under non-oxidizingconditions, andvfinally of manufacturing butter working andagglomerating the butter under from cream which consists in removing the4 incorporated free oxygen, then producing butter by churning theoxygen-freed cream under non-oxidizing conditions, and finally washing,salting and working and agglomerating the butter under non-oxidizingconditions i 8. As an improved article of manufacture, agglomeratedbutter having a normal aqueous content but substantially free fromincorporatcd oxygen.

CHESTER EARL GRAY.

lVitnesses:

C; M. GEoReusoN, J. M. Nrsson;

under rarefied conditions while in removing the I

